1. Field of the Invention
The present invention relates to a camera with a movable lens barrel. More particularly, the present invention relates to a camera which has a movable lens barrel and a flash device, and in which a flash emitting unit of the flash device is kept movable in response to movement of the movable lens barrel for unfolding and collapsing.
2. Description Related to the Prior Art
There is a flash built-in type of camera useful in taking an exposure at night or for a rear light scene. For example, U.S. Pat. No. 6,314,244 (corresponding to JP-A 2000-330168) discloses a camera with a flip-up flash device in which a flip-up flash emitting unit is movable for the purpose of protection of the flash emitting unit or preventing a red-eye phenomenon. The flash emitting unit is movable relative to a camera body between a contained position and a flashing position, and when the camera is not used, is moved to the contained position, and when the camera is used, is moved to the flashing position where the flash emitting unit protrudes from the camera body.
To exert force for moving the flash emitting unit, a motor or actuator for moving a movable lens barrel back and forth is used. When a power source for the camera is turned on for moving the movable lens barrel in the forward direction from a collapsed position, the flash emitting unit is also shifted from the contained position to the flashing position. When the power source for the camera is turned off, the movable lens barrel is moved back to the collapsed position. The flash emitting unit also shifts from the flashing position to the contained position.
If a considerably large clearance occurs between the flash emitting unit and an opening for containing the flash emitting unit set in the contained position, quality of the camera is not very high in view of good appearance of the camera. Also, excessive play of the flash emitting unit in the contained position results in low quality. Thus, it has been suggested that a stroke of a mechanism used for moving the flash emitting unit is set larger than a stroke of the flash emitting unit moving itself to the contained position. A difference between those strokes is absorbed by a biasing spring incorporated in the camera.
It is inevitable that long time elapses while the camera is carried or preserved by a user or dealer without being used. Force exerted by a spring for biasing the flash emitting unit toward the contained position is applied to plural gears which transmit motion of the motor to the movable lens barrel. Such gears for use in the camera are formed from plastic materia in view of reducing the size, weight and cost. However, it is likely the deformation of creep may occur in teeth of the plastic gears due to concentration of stress for a long time.